Most of the conventional wheel hub structure are assembled together with a number of spokes thru the holes on the hub. Usually, one end of the conventional spoke is furnished with threads, and the other bent end is formed into a rivet head. The spokes are transposingly fixed on the both sides of the hub one after another. Since one end of the spoke to be fixed to the hub has to be a rivet head by hammering process, the quality of steel being used must be slighly soft; as a result, the strength of the spoke is relatively reduced, and the serviceable life of the spoke will also be reduced.